PTAB

IPR2017-01977

TeleSign Corp v. Twilio Inc

Key Events

Petition

petition

Title: System and Method for Processing Telephony Sessions
Brief Description: The ’376 patent describes a method and system for processing telephony sessions via a call router connected to both a telephony network (e.g., PSTN) and an internet-connected application server. The system aims to simplify the creation of telephony-based applications by allowing developers to use web-service messaging formats without requiring deep expertise in complex telephony network interfacing.

Prior Art Relied Upon: Maes (Patent 6,801,604) and Ransom (Application # 2003/0204756).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that Maes discloses a system for providing IP-based applications over telephony networks that meets most limitations of the challenged claims. The Maes system includes a router, an application server, and an API for accessing telephony functions like making calls or collecting DTMF digits. However, Maes teaches using a SOAP-based API. Ransom is cited for its teaching that Representational State Transfer (REST) and SOAP are well-known, interchangeable web service models for providing interoperability between disparate systems.
- Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) reviewing Maes, which does not detail its web service technology, would have been motivated to consult references like Ransom for implementation details. Given that Ransom teaches REST and SOAP as known alternatives, a POSITA would have found it an obvious design choice to implement the functionality of Maes using a REST-based API instead of a SOAP-based one. The ’376 patent itself concedes that REST APIs were familiar to web developers.
- Expectation of Success: Because REST and SOAP were known to be functionally equivalent for providing access to API resources, a POSITA would have had a high expectation of success in substituting one for the other without any unexpected results.

Prior Art Relied Upon: Maes (Patent 6,801,604), Ransom (Application # 2003/0204756), and Jiang (Patent 7,092,370).
Core Argument for this Ground:
- Prior Art Mapping: This ground builds on the combination of Maes and Ransom to address claim 5 (initiating a session by sending an SMS message) and claim 17 (returned data is a log of calls). While the Maes/Ransom combination provides the foundational REST-based telephony system, Jiang is introduced because it explicitly teaches application-initiated SMS messaging and the storage and retrieval of call logs on a server.
- Motivation to Combine: A POSITA would have been motivated to combine Jiang’s teachings with the Maes/Ransom system to add beneficial and conventional telephony features. Integrating SMS functionality and call-log retrieval would be a predictable improvement to enhance the capabilities of the base system taught by Maes.
- Expectation of Success: The combination represented a simple addition of known features (application-initiated SMS, call logs) to a known type of system (web service telephony gateway), and therefore a POSITA would have had a high expectation of success.

Prior Art Relied Upon: ETSI ES 202 391-4 (a 2006 ETSI standard) and Ransom (Application # 2003/0204756).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner asserted that the ETSI standard teaches a system using Parlay X Web Services that allows an application to invoke telephony functions (e.g., send SMS, initiate calls) via an API without specific telecommunications knowledge, similar to the goal of the ’376 patent. The ETSI system, like Maes, is SOAP-based. Ransom is again cited for its disclosure of REST as a well-known alternative to SOAP.
- Motivation to Combine: The motivation is identical to that in Ground 1: it would have been an obvious design choice for a POSITA to implement the functionalities described in the SOAP-based ETSI standard using the alternative, well-known REST architecture taught by Ransom. This would achieve the same result of providing simplified access to telephony resources.
- Expectation of Success: A POSITA would have had a high expectation of success in applying the REST architecture to the ETSI system, as the two web service models were known to be interchangeable and would produce predictable results.
Additional Grounds: Petitioner asserted additional obviousness challenges based on combinations of ETSI ES 202 391-4, Ransom, ETSI ES 202 391-7 (for claim 17), and ETSI ES 202 391-2 (for claim 19), which relied on similar design modification theories.

Petitioner’s core technical contention, central to multiple grounds, was that prior to 2008, REST and SOAP were widely known in the art to be functionally equivalent, interchangeable architectural styles for implementing web service APIs. Petitioner argued that choosing REST over SOAP (or vice versa) was a matter of routine design choice that yielded no novel or unexpected technical result, but simply achieved the same function of accessing API resources through a different, but equally well-known, convention.

Petitioner argued that discretionary denial under §325(d) would be inappropriate. It noted that the primary reference Maes, while submitted in an Information Disclosure Statement (IDS) during prosecution of the ’376 patent, was never used in a substantive rejection or otherwise discussed by the Examiner. Petitioner cited PTAB precedent for declining to deny institution in similar circumstances where a reference was merely listed in an IDS but not substantively considered.

Petitioner requests institution of an inter partes review and cancellation of claims 1-3, 5, 14, 16-17, and 19 of the ’376 patent as unpatentable.